Carburetor



Aug. 4, 1931. c, BROWN 1,817,610

CARBURETOR Filed March 5. 1927 2 Sheets-Sheet l C. BROWN CARBURETOR Aug. 4, 1931.

2 Sheets-Sheet 2 Filed March 5 1927 ply 1 with a closure pad 0 adapted to close the e of the main throttle valve.

Patented Aug. 4, 1931 1;;

' UNETED stares Parana carries- CLEMENT BROWN, or wrrron, BIRMINGHAM, ENGLAND, asst-anon T0 AMALGAMATED LIMITED. 0F mamas-HAM ENGLAN cnnnnzanmon Application filed March 3, 1927, Serial No. 172,531, and 'in'Great Britain May 1926.

This invention comprises certain improveof internal combustion engines, and it refers particularly to that type of mixture supsystem wherein an auxiliary air inlet is provided in association with the jet in manner such that a rich mixture is delivered into the induction pipe or other region of negative pressure.

Primarily the present invention comprehends means for automatically regulating this auxiliary air inlet by or in conjunction with the operation of the control valve.

In order that this invention may be clearly understood and readily carried into practice reference may be had to the appended sheet of explanatory drawings, on which Figure 1 is a plan view of a carburetor incorporating one embodiment of the present y invention.

Figure 2 is a view similar to Figure 1 but illustrating a modified form of the present invention.

Figure 3 is a sectional elevation showing 5 the auxiliary air passages of the carburetor tion shown in the drawings the reference letter a designates a surface of the carburetor body at whlch we arrange the inlet port or opening of the auxiliary air inlet conduit appertammg'to the et. This auxil ary air inlet conduit may be associated with the jet according to any othodox methods, and if desired a constriction may be incorporated in the conduit. 7) is a lever which is provlded auxiliary air inlet conduit at the face a. This lever b which may comprehend a strip of sheet metal may be formed to a socket configuration (Z designed to embrace the spindle Between this spindle e and the socket cl a frictional engagement is provided. The member I) is capable of an angular movement limited on the one hand by the face containing the auxiliary air inlet conduits at a and on the other hand by any suitable abutment such as that indicated *by the reference letter As shown in'Figure 1, therefore, throughout the range of movement of the throttle valve any closing movement of the throttle valve has. the result that it opens the. auxiliary air inlet .port a while any openingof the throttle valve has the effect of closing the said air inlet po-rt'a. In the plan view shown in igure 1 it shouldbeexplained that the throttle valve opens by a clockwise movement, and it will be appreciated that the function of the memher 6 in nowise interferes with the ordinary operation of the throttle valve. The throttle valve operates as usual with the exception that regardless ofits position any movement in opening closes :the auxiliary air inlet at a, while any movement in closing opens the auxiliary air inlet port-at 64, the arrangement being such that a continua tion of movement of the throttle valve still leaves the member I) in its position until there is a reversal of this movement.

A convenient float feed may be incorporated comprising a floatchamber j Figures and tadapted-to supply fuel by-w-ay of a fuel passage 7cto a-removable et member 1 having a central airjinlet m. Said jet member 1 is reduced in diameter-to form-in conjunction.

with the I adjacent wall :of the carburetor an annular chamber n where richmixture is produced and from which the rich mixture passes by wayofa duct 0 to an'annularchamber p' surrounding the choke tube 9. r" is the main air inlet of the carburetor. The lever *6 car ries a leather or-other closing padoarranged to coact with the auxiliary air inlet port a which com'municateswith a vertical-airpassage 's leading "into the annular chamber 79 before referred to. In' Figure '3 the closure pad-c isshown in aclosed posit-ion as when the throttle has executed an opening m'ovement and in Figured the pad 0 associated with-{thelever bis showngin-the open-position limited by the stop 7 in which air is admitted through the inlet a for the purpose of .increasing the proportion of air when the throttle valve executes a closing ;move1nent.

Since it may be desirableto-provide that when the throttle valveis-in itsnearly closed or idling position the inlet to the auxiliary air conduit at a is closed contrary to the conditions obtaining in the embodiment shown in Figure l, we may alternatively employ a mechanism one embodiment of which is illustrated in Figure 2 in which g is the throttle valve spindle frictionally carrying the member bwhich fulfills a function similar to th at described in connection with Figure 1, but in the embodiment shown in Figure 2 the throttle valve spindle g is provided with an additional arm h which cooperates with the lever 2' in such manner that when the throttle valve is in its nearly closed or idling position as shown in Figure 2, through the intermediary of this lever 2' the member 7) is caused to close the auxiliary air inlet at the face a. So soon as any substantial opening of the throttle occurs the lever 2' no longer functions, while upon closing of the throttle valve when in an open position the member 5' is automatically displaced to open the supplementary air inlet at a, the frictional engagement between the throttle spindle g and the member I) being sufiicient to overcome any resistance which might occur as a result of the lever 2'.

Having described my invention, what I claim and desire to secure by Letters Patent 1s 1. In combination with a carburetor having an air passage, said passage having a main air inlet, an auxiliary air inlet, and an air outlet; a throttle controlling said outlet and having a spindle, a lever secured to said spindle for movement by said spindle, a clos ure arranged on said lever and adapted to close said auxiliary air inlet when the spindle is turned in the required direction to open the throttle valve and to open said air inlet when said spindle is turned in the reverse direction and means coacting with, said lever to open or close said auxiliary air inlet on a very slight movement of the throttle.

2. The carburetor as claimed in claim 1, in which the means coacting with the lever comprises a tappet arm on the throttle spindle and a second lever arranged to bear on the first named lever and having a tappet arm 7 arranged in the path of and for operation by the first named tappet arm.

3. In combination with a carburetor having an auxiliary air inlet duct which communicates directly with the main choke tube, a throttle having a spindle and means actuated by the throttle to close or open said auxiliary air inlet duct according to the direction in which the throttle is moved, said means comprising a closure carried by a lever, which lever is mounted on the spindle and has frictional contact therewith, so that the lever is moved by an initial movement of the spindle and the spindle may be further moved independently of the lever.

41-. A carburetor as claimed in claim 3, in

means to limit the eXtent of movement of the lever.

In witness whereof I aflix my signature.

C. BROWN. 

